The present disclosure relates to a vehicular seat and, more specifically, to a vehicular seat capable of housing a seat back and a seat cushion in a housing floor formed at a position lower than a vehicle body floor.
Conventionally, vehicular seats capable of housing a seat back and a seat cushion which include a seat body in a housing floor formed at a position lower than a vehicle body floor are already known, and of them, vehicular rear seats capable of housing a seat body to be folded forward in a housing floor provided in front of the seat exist, for example, see Japanese Patent Document 2009-67309 A (referred to herein as “the '309 Document”).
The vehicular seat described in the '309 Document includes a housing structure having a mounting shaft mounted to a vehicle body floor and pivotally supporting a seat back, and a leg member whose upper end supports a front portion of a seat cushion and whose lower end is pivotally held in a holding groove fixed to a housing floor. At the time of a housing operation of a seat body, the seat back rotates to move the seat cushion to the housing floor with respect to the vehicle body floor, and the retractable leg member rotates around the holding groove in conjunction with the seat back, thereby capable of housing the seat body in the housing floor. In addition, the vehicular seat is configured to be capable of switching from a “seatable” state, in which an occupant can sit thereon, to a “tip-up” state, in which the seat cushion is flipped up after detaching the retractable leg member from the holding groove.
However, in the seat capable of housing the seat body in the housing floor as described in '309 Document, component parts such as the leg member and the holding groove for supporting the seat back rotatably are mounted not only on the vehicle body floor surface on which the seat body is installed but also on the housing floor surface, which complicated the housing structure for housing the seat body. In particular, the holding groove holding the lower end portion of the leg member is fixed to the housing floor, and the total length of the leg member supporting the seat cushion is increased, so consideration was required for increasing support rigidity of the seat cushion, the leg member, and the holding groove which receive the seating load of a seated person. Therefore, a vehicular seat capable of being housed in a housing floor which has a simple structure and in which support rigidity of a seat body is increased is desirable. In addition, a vehicular seat capable of securing a wide housing space is desirable.
In addition, in the seat as described in the '309 Document, the leg member supporting the seat cushion was a long member because of being connected between the seat cushion and the housing floor. Therefore, when attaching and detaching the leg member to and from the holding groove in a switching operation of a seatable state and a tip-up state, the deflection width in the front to back direction of the detached leg member is increased due to a long total length of the leg member, so an operation of attaching the leg member to the holding groove is made difficult. Thus, a vehicular seat in which a switching operation from a seatable state is simplified is desirable.
Further, in the seat capable of switching the seat body from the seatable state, a technique capable of stably maintaining the seat body in the seatable state even if an inertial force is applied to the seat body in association with a front end collision or a rear end collision of a vehicle is desirable.